Donald Trump’s oldest son, a primary surrogate for his presidential candidacy, alluded on Thursday to the mass killing of Jewish people in Nazi Germany while laying out what he sees as a media double standard in campaign coverage.

In an interview with Chris Stigall on Talk Radio 1210 WPHT, Donald Trump Jr. made the argument that Republicans would be punished if they lied or schemed in fashions similar to Democratic candidate Hillary Clinton’s campaign. And then he decided to talk about gas chambers.

“The media has been her number one surrogate in this. Without the media, this wouldn’t even be a contest, but the media has built her up,” Trump Jr said. “They’ve let her slide on every indiscrepancy [sic], on every lie, on every DNC game trying to get Bernie Sanders out of this thing. If Republicans were doing that, they’d be warming up the gas chamber right now.”

A reference to gas chambers is the type of remark that under typical campaign conventions would be met with profound rebuke and alarm. But while criticism came in quickly on Twitter, a senior member of the Republican National Committee still blasted out the interview.

Trump Jr. has gone down similar paths before. As the group RightWingWatch noted, he has “posted an image to Instagram that included “Pepe the frog,” which, according to the Southern Poverty Law Center, is a meme “constantly used by white supremacists” and “appeared on a radio show with James Edwards, host of the white supremacist radio show Political Cesspool.”

The Trump campaign has also been accused in the past of pushing anti-Semitic memes. Donald Trump himself got into trouble over the summer for tweeting an image of Clinton pasted over money with a Jewish star badge next to her.

Trump Jr. told NBC News on Thursday that he was referring to capital punishment, not the Holocaust. The reaction from some anti-Semitic Trump supporters on Twitter, however, suggests that they comfortably took it as a Holocaust reference.

Trump, Jr. appeared on ABC’s “Good Morning America” Friday and again denied he was making a Holocaust reference, though he did say his statement was “a poor choice of words perhaps.”

This post has been updated to include Trump Jr.’s later defenses of his remark. Language has been adjusted to indicate that Donald Trump Jr. told NBC he meant capital ― not, as NBC earlier tweeted, corporal ― punishment.